Retarding mechanism for photographic shutters



May 25, 1937. A. BARENYI RETARDING MECHANISM FOR PHOTOGRAPHIC SHUTTERSFiled Nov. 20, 1935 W 5 a? v 47 ynusntor ilk/way Patented May 25, 1937PATENT OFFICE RETABDING MECHANISM FOR PHOTO- GBAPHIC SHUTTERS Ar idBarnyi,

signal to Voigtlander & schaft, Brunswick, Germany November 20, 1935,Serial No. 50,756

November 2'7, 1934 Application In Germany 2 Claims.

My invention relates to improvements in re tarding mechanisms forphotographic shutters, and more particularly in retarding mechanisms ofthe type comprising an escape wheel and an anchor or pallet cooperatingtherewith for controlling the retarding action of the said mechanism.The object of the improvements is to pro lide a mechanism of this typeby means of which the retarding action may be accurately varied withinbroad limits, and with this object in view my invention consists inproviding means for varying the range of the swinging movement of theanchor or pallet and the depth of engagement thereof in the teeth of theescape wheel.

For the purpose of explaining the invention an example embodying thesame has been shown in the accompanying drawing in which the samereference characters have been used mall the views to indicatecorresponding parts. In said drawing Fig. 1 is a fragmentary elevationof the shutter with the plate closing the shutter casing removed andcertain parts broken away, the pallet being shown in the position inwhich it is in full engagement with the teeth of the escape wheel and inwhich it is capable of wide swinging movement,

Fig. 2 is a similar elevation showing the pallet in the positionretracted away from the escape wheel, so that the depth of engagementbetween the same and the teeth of the escape wheel and also the range ofthe swinging movement are reduced,

Fig. 3 is a top plane view of Fig. 2 viewed in the direction oi thearrows 3-3,

Fig. 4 is a diagrammatical detail elevation showing the escape mechanismdetached from the retarding mechanism, the parts being in the sameposition as in Fig. 1, and

Fig. 5 is a similar elevation showing the parts in the same position asin Fig. 2.

For the purpose of explaining the invention I shall describe the same inconnection with a retarding mechanism controlling the shutter operatingmechanism and the time of exposure, but I wish it to be understood thatmy invention is not limited to the use in suchretarding mechanisms.

In the example shown having a central exposure or lens opening 2normally closed by the blades (not shown). Upon a partition member 3most the shutter operating mechanism including a motor or master on abolt IS, a pinion with a gear -wheel Berlin-Steglitz, Germany, as-

Sohn Aktiengesellmember 4 and the retarding mechanismthereof is carried.The motor or master member comprises a housing having a spiral springconfined therein, which spring is connected with one end to the housingand with its opposite end to an arbor 6 carrying a setting lever I. Thesaid housing is formed with lugs 8, and the setting lever is connectedwith a disk 9 formed with teeth 10. The said lugs and teeth are engagedrespectively by latches H and 12 connected with the operating mechanism.The housing 5 is'formed with gear teeth 13 engaging in a pinion l4connected with the shutter operating mechanism (not shown). As is knownto those skilled in the art by rocking the setting lever l inanti-clockwise direction the spring is put under tension, whereupon thedisk 9 and the arbor 6 are locked in position by the latch l2.Thereafter the housing likewise tends to turn in anti-clockwisedirection, but for the present it is locked in position by the latch llengaging one of the lugs 8. When the latch H is retracted from the saidlug by the operating mechanism the housing rotates in anti-clockwisedirection and such rotary movement is transmitted by means of the saidgear, teeth and the pinion M to the shutter operating mechanism. On thepartition member 3 and a plate l5 connected therewith a retardingmechanism is mounted which comprises a pinion it connected with a gearwheel l1 and rotatably mounted therewith l9 meshing with the gear wheel11 and a gear wheel 20 connected therewith and both mounted on a bolt2|, a pinion 22 meshing with the gear wheel 20 and connected 23 and bothmounted on a bolt 24, a pinion 25 meshing with the gear wheel 23 andconnected with an escape wheel 21 and both mounted on a bolt 26, and ananchor or pallet 28 engaging in the teeth of thesaid escape wheel andmounted on a bolt 29. On a bolt 32 a lever 3| is rockingly mounted whichis formed with a toothed sector 33 meshing with the pinion l6, and thesaid lever is formed with a heel 33 located in'position for engagementwith the lugs 8 of the housing 5, and a spring 34 acting on the lever 3|tends to rock the same in anticlockwise direction and into the positionshown in Fig. 1.

The mechanism so ation are known in the art, necessary to describe thesame more in detail. But for a detailed description reference is madefar described and its oper- "tO Patents NOS. 1,828,215 and 1,843,265granted and I deem it not pends on the position to me respectivelyOctober 20, 1931 and February 2, 1932.

Referring now to the parts to which my in vention more particularlyrelates, the pivot bolt 2! on which the pallet or anchor II is mountedis not fixed to the partition member 3, but it is mounted on an arm of abell crank lever 31 pivotally mounted on a pin 36 fixed to-a lug llcarried by the partition member I. To the other arm or the said bellcrank lever a pin 3! is fixed, which is in engagement with a slot 40made in a ring I rotatably mounted on a lens tube .2 fixed to thepartition member 3. The said ring 4| carries a pin ll passed outwardlythrough a slot N made in the plate I5 and carrying a button by means ofwhich the ring ll may be moved by hand from the outside oi the shuttercasing in circumferential direction.

To the partition I a pin is secured which engages in an outwardlyflaring cut-out portion 18 made in a rearwardly extending heel 41 of theanchor or pallet 28.

The retarding action of the mechanism de- 01 the anchor or pallet 28relatively to the escape wheel 2'! and the pin 45. When the said palletis in the position shown in Fig. 1 in which its lips are in fullengagement with the teeth 01' the escape wheel 21 and the pin ll acts onthe outer portions of the heel 41 thus permitting a large range or theswinging movement or the pallet, the retarding action oi? the pallet islarge by reason of the said large range of movement, and when the palletis set into the position shown in Fig. 2 in which its lips engage theouter ends of the teeth of the escape wheel and the pin 45 engages theinner part of the cut-out portion 46, the range of movement 01 thepallet is small, and therefore its retarding action is likewise small.

I have found, that by merely varying the range oi. movement of thepallet without simultaneously varying the engagement of the lips oi thepallet with the teeth of the escape wheel exact regulation of theretarding action is not attained, because when the mechanism is startedwith the pallet in the position shown in Fig. 1 it takes some timebei'ore the pallet swings through its full range of movement. However,in the construction shown in the figures in which the lips of the palletare in full engagement with the teeth of the escape wheel the palletswings through the whole range of movement, and therefore it has itsfull retarding action from the beginning of the operation.

I claim:

1. Retarding mechanism for the shutters of photographic cameras,comprising an escape wheel and a pallet cooperating therewith, said;pallet being formed at the side 01' its pivot remote from its lips withan outwardly flaring cutout portion, a, stop passed through said cut-outportion, and means adapted to be operated from the outside of theshutter casing for shifting the said pallet with its pivot bolt towardsand away from said escape wheel and relatively to said stop.

2. Retarding mechanism for the shutters of photographic cameras,comprising an escape wheel, and a pallet cooperating therewith, a stopadapted to limit the range oi. movement of said pallet, and means forbodily moving the said pallet towards and away from said escape wheeland relatively to said stop, said stop and the portion of said palletwhich cooperates therewith being shaped so that the play of the palletrelatively to the stop is reduced as the pallet is moved away from theescape wheel.

ARPAD BARENYI.

